A recent study by Josh Makower, MD, and a team of researchers from Stanford University found that, on average, medical device companies spend $31 million to bring a low-to-medium-risk device to market. Furthermore, the study finds the time it takes to do so is an average of 10 months for the regulatory approval process alone. While the report is controversial in resting its sights on the FDA for unduly burdening the development process, developers of medical devices must also claim responsibility by searching earnestly for areas where they can exercise cost and time-to-market controls. The early use of modeling and simulation offers one such opportunity.

Fig. 1 - Lifespan’s Medical Simulation Center located at Rhode Island Hospital in Providence, RI. Simulation facilities allow for rapid and, if necessary, frequent simulated use testing, potentially smoothing the path to regulatory approval.
In the medical devices arena, simulated use testing drives an iterative process: test, identify potential concerns, refine, and re-deploy. The sooner simulation is employed in the design process, the more opportunity there is for risk intervention and reduction. That translates to lower development costs, shortened time to bring a product to market, greater patient safety, a potentially smoother path to regulatory approval, and enhanced market acceptance. It is important to consider three key elements to employ simulation in the most cost-and time-effective manner: rapid prototyping, cross-functional teams in simulation, and on-site simulation facilities.

(1) Rapid Prototyping

The ability to rapidly prototype means several versions of a device may be created and available to test immediately, or in rapid succession — potentially revealing flaws in the crucial early stages of the development process. Many devices undergo prototyping only in the later stages of a project, depriving the design team of the potential benefits of seeing a model early on in the design process, when shortcomings can be addressed more easily.

Putting a device into users’ hands allows for formative testing that provides the design team with a wealth of benefits. It helps dispel any incorrect assumptions one may have about user preferences, offers the “early intervention” opportunity to identify sub-optimal use characteristics that may cause risk to patient safety, and guides refinement of the user interface. In fact, formative usability tests may inform and speed up the remainder of the design process better than any project brief.

One significant reason that medical device manufacturers resist formative simulation testing is the perceived cost of prototyping. However, today’s rapid prototyping technology puts fairly production-equivalent pieces in the hands of users for simulated use testing quickly and relatively inexpensively. Plastic parts may be modeled using CAD and 3D-printing technologies, services now available in-house at the more sophisticated design firms. Electronic circuit boards may be fabricated and hand-assembled in small quantities in a matter of days, and at less expense than a production house can do it. A small system, such as a handheld device, may be affordably prototyped in small quantities and with nearly full functionality in less than two months’ time.

Compare this to a more traditional, production-oriented path where tooling design time, tooling costs, and other non-recurring setup charges are at stake. A system with a few dozen components might require hundreds of thousands of dollars in man-effort, several more hundred thousand dollars in tooling costs, and many months to produce. The evolution of rapid prototyping techniques has reduced the cost and development risk associated with spinning multiple revisions of a product. This has led to an increased ability and willingness to refine functionality and usability through formative studies with actual users.

To cite a recent example at Ximedica, a handheld device’s handle grip configuration was refined twice in separate formative studies to improve operator dexterity with the device, leading to improved targeting of the device on the patient treatment site. A functionally complete prototype device was supplied for the studies in order to appropriately model the complete use scenario.

(2) Involving Cross-Functional Teams in the Simulation

When cross-functional teams participate in the simulation, preliminary results are immediately apparent and collaborative problem solving can begin sooner to smooth the way to the next iteration.

When designers and engineers join program managers and researchers in the simulation observation room, four lenses have been applied and good synergies have a chance to happen. In a simulation center, the device development team is doing primary research. They have an opportunity to see the users’ constraints firsthand, dispel preconceived notions, get a feel for the environmental influences exerted by both the place and the user group dynamic, and if the simulation center is the actual clinical setting, the development team may gain insight into the product lifecycle, including storage, transportation, set-up, processing, and possibly disposal of the device or its components.

In a recent simulation of a critical clinical procedure, a team from Ximedica watched as the nurses repositioned a mannequin that represented an anesthetized patient. Witnessing the actual maneuver gave rise to in-depth discussion and several subtle device refinements.

Integrating more of the device development team into the simulated use observation will help team members to own the research by having a stake in it. And as risk is identified in the simulation, the foundation for a collaborative approach to mitigation has been laid.

(3) On-Site Simulation Facilities

An on-site simulation facility allows for rapid and, if necessary, frequent simulated use testing. Certainly, fullscale, thoroughly equipped simulation centers are especially cost-effective when they may be shared among many users; however, an on-site simulation center that can reasonably invoke a clinical setting still provides great value. It encourages more simulation more often and provides device developers with the flexibility to arrange the setting with key features.

Such facilities may also help meet regulatory demands. Increasingly, the FDA is looking for evidence provided by simulations performed in realistic settings that include sight and sound distractions. Simulated clinical settings also offer benefits that go well beyond regulatory compliance. In realistic environments, users can more easily recall and replicate their ordinary routines and procedures. The familiarity of the surroundings eases communication between the researcher and the user, and yields richer, more complete data on which to rely.

Rapid prototyping of production-equivalent and early-stage models, involving cross-functional teams in the simulation observation, and having a flexible simulation facility on site where the device design takes place can contribute a great deal to meeting or beating product development timelines by identifying and contributing to the mitigation of use error risks early in the development process. Also of consequence, device designers using these tools reach the regulatory review stages better armed for approval. Furthermore, because the resulting device refinements have been made at earlier stages, the changes have been made cost effectively.

This article was written by Aidan Petrie, CIO for Ximedica, Providence, RI. For more information, Click Here .